(4R)-(-)-2-(Nicotinoylamino)ethyl 3-nitrooxypropyl 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydro-3,5-pyridinedicarboxylate (1), a new calcium antagonist, was synthesized via both enantioselective hydrolysis and transesterification of prochiral bis[2-(nicotinoylamino)ethyl]ester .2HCl (5) by using enzymes. Hydrolysis of 5 by proteases originated from Aspergillus melleus and Bacillus licheniformis etc. in aqueous media afforded (4R)-(-)-3-[2-(nicotinoylamino)-ethoxycarbonyl]-2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-5-carboxylic acid (6) in more than 99% e.e., which was converted to 1 by esterification with 3-nitrooxypropyl bromide. Enzymatic transesterification of 5 with 3-nitrooxypropanol gave 1 in more than 99.5% e.e. directly.
(4R)-(-)-2-(烟酰
氨基)乙基
3-硝氧基丙基 2,6-二甲基-4-(3-
硝基苯基)-1,4-二氢-3,5-
吡啶二
羧酸酯 (1),一种新的
钙拮抗剂,是通过酶介导的前手性双[2-(烟酰
氨基)乙基]酯·2HCl (5) 的不对称
水解和转酯反应合成的。在
水溶液中,来自曲霉属和枯草杆菌的
蛋白酶等对5进行
水解,得到(4R)-(-)-3-[2-(烟酰
氨基)乙氧基羰基]-2,6-二甲基-4-(3-
硝基苯基)-1,4-
二氢吡啶-5-
羧酸 (6),其对映体过量(ee)超过99%。随后,6通过与
3-硝氧基丙基
溴进行酯化反应转化为1。此外,5与
3-硝氧基
丙醇在酶催化下进行转酯反应,直接得到超过99.5% ee的1。